<title>骑马修栅栏</title><link href="http://hzoi.com/tomorrow.css" rel="stylesheet"><div class="ui existing segment"><pre><code><span class="pl-cm">/*</span>
<span class="pl-cm">6</span>
<span class="pl-cm">4 3</span>
<span class="pl-cm">2 1</span>
<span class="pl-cm">1 3</span>
<span class="pl-cm">3 4</span>
<span class="pl-cm">3 2</span>
<span class="pl-cm">5 1</span>
<span class="pl-cm">*/</span>
<span class="pl-cm">/*******************</span>
<span class="pl-cm">	Author  : Zhang Haoling</span>
<span class="pl-cm">	Filename: 1.cpp</span>
<span class="pl-cm">	Date    : 2020-01-09 09:22:44</span>
<span class="pl-cm">********************/</span>
<span class="pl-cp">#include</span><span class="pl-cpf">&lt;cstdio&gt;</span><span class="pl-cp"></span>
<span class="pl-cp">#include</span><span class="pl-cpf">&lt;iostream&gt;</span><span class="pl-cp"></span>
<span class="pl-cp">#include</span><span class="pl-cpf">&lt;algorithm&gt;</span><span class="pl-cp"></span>
<span class="pl-cp">#include</span><span class="pl-cpf">&lt;cstring&gt;</span><span class="pl-cp"></span>
<span class="pl-cp">#define maxn 2001</span>
<span class="pl-k">using</span> <span class="pl-k">namespace</span> <span class="pl-n">std</span><span class="pl-p">;</span>
<span class="pl-kt">int</span> <span class="pl-n">g</span><span class="pl-p">[</span><span class="pl-n">maxn</span><span class="pl-p">][</span><span class="pl-n">maxn</span><span class="pl-p">],</span><span class="pl-n">du</span><span class="pl-p">[</span><span class="pl-n">maxn</span><span class="pl-p">],</span><span class="pl-n">path</span><span class="pl-p">[</span><span class="pl-n">maxn</span><span class="pl-p">],</span><span class="pl-n">n</span><span class="pl-p">,</span><span class="pl-n">m</span><span class="pl-p">,</span><span class="pl-n">tot</span><span class="pl-p">,</span><span class="pl-n">x</span><span class="pl-p">,</span><span class="pl-n">y</span><span class="pl-p">,</span><span class="pl-n">start</span><span class="pl-p">;</span>
<span class="pl-kt">void</span> <span class="pl-nf">find</span><span class="pl-p">(</span><span class="pl-kt">int</span> <span class="pl-n">i</span><span class="pl-p">){</span>
	<span class="pl-c1">//printf(&quot;%d\n&quot;,i);</span>
	<span class="pl-k">for</span><span class="pl-p">(</span><span class="pl-kt">int</span> <span class="pl-n">j</span><span class="pl-o">=</span><span class="pl-mi">1</span><span class="pl-p">;</span><span class="pl-n">j</span><span class="pl-o">&lt;=</span><span class="pl-n">n</span><span class="pl-p">;</span><span class="pl-n">j</span><span class="pl-o">++</span><span class="pl-p">){</span>
		<span class="pl-k">if</span><span class="pl-p">(</span><span class="pl-n">g</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">][</span><span class="pl-n">j</span><span class="pl-p">]</span> <span class="pl-o">&amp;&amp;</span> <span class="pl-n">i</span><span class="pl-o">!=</span><span class="pl-n">j</span><span class="pl-p">){</span>
			<span class="pl-n">g</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">][</span><span class="pl-n">j</span><span class="pl-p">]</span><span class="pl-o">--</span><span class="pl-p">;</span>
			<span class="pl-n">g</span><span class="pl-p">[</span><span class="pl-n">j</span><span class="pl-p">][</span><span class="pl-n">i</span><span class="pl-p">]</span><span class="pl-o">--</span><span class="pl-p">;</span>
			<span class="pl-n">find</span><span class="pl-p">(</span><span class="pl-n">j</span><span class="pl-p">);</span>
		<span class="pl-p">}</span>
	<span class="pl-p">}</span>
	<span class="pl-n">path</span><span class="pl-p">[</span><span class="pl-n">tot</span><span class="pl-o">++</span><span class="pl-p">]</span><span class="pl-o">=</span><span class="pl-n">i</span><span class="pl-p">;</span>
<span class="pl-p">}</span>
<span class="pl-kt">int</span> <span class="pl-nf">main</span><span class="pl-p">(){</span>
	<span class="pl-n">freopen</span><span class="pl-p">(</span><span class="pl-s">&quot;fence.in&quot;</span><span class="pl-p">,</span><span class="pl-s">&quot;r&quot;</span><span class="pl-p">,</span><span class="pl-n">stdin</span><span class="pl-p">);</span>
	<span class="pl-n">freopen</span><span class="pl-p">(</span><span class="pl-s">&quot;fence.out&quot;</span><span class="pl-p">,</span><span class="pl-s">&quot;w&quot;</span><span class="pl-p">,</span><span class="pl-n">stdout</span><span class="pl-p">);</span>
	<span class="pl-n">scanf</span><span class="pl-p">(</span><span class="pl-s">&quot;%d&quot;</span><span class="pl-p">,</span><span class="pl-o">&amp;</span><span class="pl-n">m</span><span class="pl-p">);</span>
	<span class="pl-k">for</span> <span class="pl-p">(</span><span class="pl-kt">int</span> <span class="pl-n">i</span> <span class="pl-o">=</span> <span class="pl-mi">0</span><span class="pl-p">;</span> <span class="pl-n">i</span> <span class="pl-o">&lt;</span> <span class="pl-n">m</span><span class="pl-p">;</span> <span class="pl-n">i</span><span class="pl-o">++</span><span class="pl-p">){</span>
		<span class="pl-n">scanf</span><span class="pl-p">(</span><span class="pl-s">&quot;%d%d&quot;</span><span class="pl-p">,</span><span class="pl-o">&amp;</span><span class="pl-n">x</span><span class="pl-p">,</span><span class="pl-o">&amp;</span><span class="pl-n">y</span><span class="pl-p">);</span>
		<span class="pl-n">g</span><span class="pl-p">[</span><span class="pl-n">x</span><span class="pl-p">][</span><span class="pl-n">y</span><span class="pl-p">]</span><span class="pl-o">++</span><span class="pl-p">;</span>
		<span class="pl-n">g</span><span class="pl-p">[</span><span class="pl-n">y</span><span class="pl-p">][</span><span class="pl-n">x</span><span class="pl-p">]</span><span class="pl-o">++</span><span class="pl-p">;</span>
		<span class="pl-n">du</span><span class="pl-p">[</span><span class="pl-n">x</span><span class="pl-p">]</span><span class="pl-o">++</span><span class="pl-p">;</span>
		<span class="pl-n">du</span><span class="pl-p">[</span><span class="pl-n">y</span><span class="pl-p">]</span><span class="pl-o">++</span><span class="pl-p">;</span>
		<span class="pl-n">n</span><span class="pl-o">=</span><span class="pl-n">max</span><span class="pl-p">(</span><span class="pl-n">n</span><span class="pl-p">,</span><span class="pl-n">max</span><span class="pl-p">(</span><span class="pl-n">x</span><span class="pl-p">,</span><span class="pl-n">y</span><span class="pl-p">));</span>
	<span class="pl-p">}</span>
	<span class="pl-n">start</span><span class="pl-o">=</span><span class="pl-mi">1</span><span class="pl-p">;</span>
	<span class="pl-k">for</span> <span class="pl-p">(</span><span class="pl-kt">int</span> <span class="pl-n">i</span> <span class="pl-o">=</span> <span class="pl-mi">1</span><span class="pl-p">;</span> <span class="pl-n">i</span> <span class="pl-o">&lt;=</span> <span class="pl-n">n</span><span class="pl-p">;</span> <span class="pl-n">i</span><span class="pl-o">++</span><span class="pl-p">){</span>
		<span class="pl-k">if</span><span class="pl-p">(</span><span class="pl-n">du</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">]</span><span class="pl-o">%</span><span class="pl-mi">2</span><span class="pl-p">){</span>
			<span class="pl-n">start</span><span class="pl-o">=</span><span class="pl-n">i</span><span class="pl-p">;</span>
			<span class="pl-k">break</span><span class="pl-p">;</span>
		<span class="pl-p">}</span>
	<span class="pl-p">}</span>
	<span class="pl-n">find</span><span class="pl-p">(</span><span class="pl-n">start</span><span class="pl-p">);</span>
	<span class="pl-k">for</span><span class="pl-p">(</span><span class="pl-kt">int</span> <span class="pl-n">i</span><span class="pl-o">=</span><span class="pl-n">tot</span><span class="pl-o">-</span><span class="pl-mi">1</span><span class="pl-p">;</span><span class="pl-n">i</span><span class="pl-o">&gt;=</span><span class="pl-mi">0</span><span class="pl-p">;</span><span class="pl-n">i</span><span class="pl-o">--</span><span class="pl-p">){</span>
		<span class="pl-n">printf</span><span class="pl-p">(</span><span class="pl-s">&quot;%d</span><span class="pl-se">\n</span><span class="pl-s">&quot;</span><span class="pl-p">,</span><span class="pl-n">path</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">]);</span>
	<span class="pl-p">}</span>
	<span class="pl-k">return</span> <span class="pl-mi">0</span><span class="pl-p">;</span>
<span class="pl-p">}</span>
</cpde></pre></div>